SU1109935A1 - Device for receiving signals with linear frequency modulation - Google Patents

Abstract

A DEVICE FOR RECEPTION OF SIGNALS WITH LINEAR FREQUENCY MODULATION, containing the first and second signal detection and filtering units, a decisive unit, the first input of which is connected to the output of the synchronization unit, the input of which is connected to the first inputs of the first and second mixers, the outputs of which are connected to the inputs of the synchronization unit The first and second separation filters, wherein the outputs of the first and second reference oscillator are connected to the second inputs of the first and second mixers, respectively, characterized in that purpose of noise immunity povsheni reception in multipath channel, the introduced third and fourth reference oscillation generators, third and fourth dividing filters, the third and fourth mixers, third and fourth detection units, and filtering the signals. the first and second adders, the signal processing unit and the shaper of even and odd sync signals, the input of which is connected to the output of the synchronization unit, the input of which is connected to the first inputs of the third and fourth mixers, the second inputs of which are connected to the outputs of the third and fourth generators respectively oscillations, the inputs of which are connected to the first output of the shaper of even and odd sync signals, the second output of which is connected to the inputs of the first and second oscillator of the reference oscillations, and in the first, second, third and fourth separation filter moves are connected to the corresponding inputs of the signal processing unit, with the first, second, third and fourth outputs of which are connected to the inputs of the first, second, third and fourth signaling and filtering units, respectively, of the first and third outputs The detection units and the filtering circuit of the signals are connected to the inputs of the first adder, which co-connected the output of which is connected to the second input of the decision unit, the third input of which is connected to the output of the second ummatora having inputs connected to the outputs of the second and fourth detection units, and filtering the signals, and the outputs of the third and fourth mixers, respectively connected to the inputs of the third and fourth separation filters.

Description

1 1 The invention relates to radio communications and can be used in data transmission technology. A device for receiving signals with linear frequency modulation is known, comprising a conversion and selection unit, the output of which is connected to a search and synchronization unit and inputs of information channel correlators, the outputs of which are connected to the inputs of a decision unit whose output is connected to the input of a matching unit , the generators of the copies of the reference signal, the inputs of which are connected to the corresponding outputs of the block of interferences and synchronization l. A disadvantage of this device is the design complexity. The closest technical solution to the invention is a device for receiving signals with linear frequency modulation, comprising first and second detection and filtering units, the decisive unit whose first input is connected to the output of a synchronization unit, the input of which is connected to the first inputs of the first and the second mixers, the outputs of which are connected to the inputs of the first and second separation filters, respectively, and the outputs of the first and second reference oscillator generators are connected to the second inputs of the corresponding venno first and second mixers 2. However, the known device has low immunity. The purpose of the invention is to increase the noise immunity of the reception in a multipath channel. This goal is achieved in that the device for receiving signals with linear frequency modulation, containing the first and second detection and filtering units, a decisive unit, the first input of which is connected to the output of the synchronization unit, whose input is connected to the first inputs of the first and second mixers whose outputs are connected to the inputs of the first and second separation filters, respectively, and the outputs of the first and second reference oscillator are connected to the second inputs of the first and second mixes, respectively It introduced the third and fourth reference oscillators, the third and fourth separation filters, the third and fourth mixers, the third and fourth signal detection and filtering units, the first and second adders, the signal processing unit and the even and odd sync signal generator, whose input is connected to the output synchronization unit, the input of which is connected to the first inputs of the third and fourth mixers, the second inputs of which are connected to the outputs of the third and fourth oscillator reference oscillators, respectively the inputs of which are connected to the first output of the even and odd sync driver, the second output of which is connected to the inputs of the first and second reference oscillator, and the outputs of the first, second, third and fourth separation filters are connected to the corresponding inputs of the signal processing unit, first, second , the third and fourth outputs of which are connected to the inputs of the first, second, third and fourth blocks of detection and filtering of signals, respectively, the outputs of the first and third blocks of detection signal filtering is connected to the inputs of the first adder, the output of which is connected to the second input of the decision unit, the third input of which is connected to the output of the second adder, whose inputs are connected to the outputs of the second and fourth detection and filtering units, and the outputs of the third and fourth mixers are connected to inputs of the third and fourth separation filters, respectively. FIG. 1 shows a structural electrical circuit of the proposed device; in fig. 2 is a structural electrical circuit of a signal processing unit; in fig. 3 is a time chart illustrating the operation of the device. A device for receiving signals with linear frequency modulation contains first, second, third and fourth mixers 1-4, first, second, third and fourth generators 5-8 reference oscillations, first, second, third and fourth separation filters 9-12, first , second, third and fourth blocks 13-16 for detecting and filtering signals, first and second adders 17 and 18, solving 15 block 19, synchronization block 20, even and odd synchronizer 3110 shaper, signal processing block 22. The signal processing unit contains adders 23, multipliers 24, auxiliary generator 25, narrow-band filters 26, multipliers and filters 27, adder 28. The device operates as follows. The signals of the rays L, Lg, ..., Lz (Fig. 3) are converted by frequency in mixers x 1-4 into segments of harmonic oscillations L ;, L, ..., L with duration T and frequencies f the values of which depend on latency values of the rays. If the voltages G and G of oscillations of the generators 5-8 of the reference oscillations have a doubled period of 2T / G; and G (Fig. 3) do not need to enter a guard interval, and the delays of wide-band signals in the beams of € correspond to the frequency shifts of the UEband signals L; (, ..., L with the spectrum bandwidth af "P, where F is the signal bandwidth with linear frequency modulation. These beam signals are further divided in frequency by a comb of dividing filters -9-12, and then subjected to weighting and coherent processing. addition in block 22 signal processing, complete, for example In Fig. 2. The operation of this block is that each of the separated signals in separation filters 9-12 is multiplied in multipliers 24 with the voltage of the auxiliary generator 25, and in the narrowband filters 26 there are differential frequency signals, a band the transmissions of which are inversely proportional to the width of the fading spectrum. They have amplitudes and phases, corresponding to L, which radiate to each given L, These signals are again multiplied in multipliers and filters 27 with their own signals at the outputs of split filters 9-12 and total frequencies that, up to phase, coincide with the frequency of auxiliary generator 25. At the same time, the amplitudes of the signals at the outputs of the separation filters 9-12 are multiplied by an amount proportional to the average amplitude of the signal of the given beam. At the input, for example, of the signal detection and filtering unit 13, signals are received after coherently adding in adder 28 during weight processing, which consists in each of the summands in the sum of the signals at the output of adder 28 proportional to the intensity of a given beam. After detecting odd and even parcels in blocks 13–16, the signals are detected and filtered, they are added using adders 17 and 18 separately in paths 1 and O. To make a decision about the transferred voltage symbol, they are compared in a decisive block 19. Synchronism of separate processing of odd and even packages on the 2T signal processing interval are provided by sync pulses at the outputs of the shaper 21 even and odd sync pulses. The pulses at its outputs set the moments of the launches of the generators 5-8 reference oscillations. Since the parcels are processed in the 2T interval, the decision points in decision block 19 specify the pulses of the synchronization block 20 by sending No. 1 at time tj (Fig. 3), by sending No. 2 at time tj, etc. The proposed device provides the addition of delayed signals due to multipath, which allows for a more complete use of their energy at the reception, as a result of which the interference immunity of reception increases.

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Claims (1)

DEVICE FOR RECEIVING SIGNALS WITH LINEAR FREQUENCY MODULATION, containing the first and second signal detection and filtering units, a decision unit, the first input of which is connected to the output of the synchronization unit, the input of which is connected to the first inputs of the first and second mixers, the outputs of which are connected to the inputs of the first, respectively and a second separation filter, and the outputs of the first and second generators of reference oscillations are connected to the second inputs of the first and second mixers, respectively, characterized in that, for the purpose improve search in the multipath noise immunity receiving channel administered third, and fourth reference oscillation generators, third and fourth dividing filters, the third and fourth mixers; the third and fourth signal detection and filtering units, the first and second adders, the signal processing unit and the even and odd clock signal generator, the input of which is connected to the output of the synchronization unit, the input of which is connected to the first inputs of the third and fourth mixers, the second inputs of which are connected to the outputs respectively, the third and fourth he. reference oscillators, the inputs of which are connected to the first output of the even and odd clock signal generator, the second output of which is connected to the inputs of the first and second reference oscillators, the outputs of the first, second, third and fourth separation filters connected to the corresponding inputs of the signal processing unit, the first, the second, third and fourth outputs of which are connected to the inputs of the first, second, third and fourth signal detection and filtering units, respectively, the outputs of the first and the fifth signal detection and filtering units are connected to the inputs of the first adder, the output of which is connected to the second input of the deciding unit, the third input of which is connected to the output of the second adder, the inputs of which are connected to the outputs of the second and fourth signal detection and filtering units, and the outputs of the third and fourth mixers connected to the inputs of the third and fourth separation filters, respectively. SU di) 1109935>